content='aggcacggaaaaacgggaataacggaggaggacttggcacggcattacacggaggcggaggacaaacgggatggcggtattggaggtggcggactgttcgggga'+\
         'gggacggatacggattctggccacggacggaaaggaggacacggcggacatacaatggataacggaaacaaaccagacaaacttcggtagaaatacagaagctta'+\
        'cggctggcggacaacggactggcggattccaaaaacggaggaggcggacggaggc'

def findLen(c):
    return len([i for i in content if i==c])

print(findLen('a'))
print(findLen('g'))
print(findLen('c'))
print(findLen('t'))
